1999-2004 4V Mustang owners now have something to cheer about! American Racing Headers now has long tube header systems for you. Manufactured from 304 stainless steel, ARH's longtube systems are engineered for a great fit and outstanding horsepower and torque gains throughout the RPM range. Positioned wide in engine compartment to allow easy transmission removal. Made in the U.S.A.

*Off-Road X-pipes do not have any catalytic converters and are not EPA street legal. They are manufactured and represented for the purpose of OFF-ROAD RACE USE ONLY!*Available with or without EGR fittings.

By Bill Tumas:
If you're like me, you're always looking for ways to make more power out of your Mustang. We get a lot of customers that have the basic bolts on, such as a tune, cold air kit, and pulleys, but are looking to something more involved to take their car to the next level. For years, hot-rodders have always looked at headers as a good way to make power. With the modern Mustangs, that's no different.

Today we're going to take a look at the American Racing Headers. We've been installing a lot of American Racing Headers in the shop lately, and with good reason. We put a set in our 2013 Gotta Have It Race car and picked up over 30 horsepower at the tires with no additional changes. American Racing offers headers for all '99 and up Mustangs in varying sizes, from 1-5/8, all the way up 2 inch primary tubes for your race versions, making over a thousand horsepower.

All sizes of American Racing Headers are all going to come with this 3/8 inch flange. It's laser cut and fits well enough in certain applications, it doesn't even require a gasket. The kits are going to come with a matching 2 1/2 or 3 inch X-pipe. Welded on bungs for your O2 sensors and they're available with or without catalytic converters. If you opt to go with converters, American Racing offers this nice small efficient catalytic converter. The inside is a 200 cell metallic substrate allowing high flow while still keeping you legal.

Let's take a closer look at the header. This particular header is going to fit your 2011 and up 5.0 liter Mustangs. If you take a look, you can see how smooth the transition is between your flange and the primary. In this particular header, all your primaries are equal length and 1-7/8 inches in diameter, flowing downward to a merge style collector with a scavenger's spike built inside to produce the most power and torque. Here you can get a better look at the merge collector itself with the scavenger's spike in the middle to separate the exhaust coming through it. American Racing provides everything you need for high quality installation including bolts, oxygen extension harnesses, as well as an online forum where you can ask technical questions or show off your installation once you're finished.

We have our 2013 Gotta Have It Race car up on the lift, so we can show you how well the American Racing Headers fit. If you look, there's plenty of space between the header and the frame, while still keeping plenty of room in the center allowing you to remove your transmission without having to remove the header. It's plenty of space around our starter and the steering shaft, which can be an issue with other headers, has enough space that I can even get my hand between the shaft and the header. It's plenty of room, plenty of clearance, excellent fitting header.

American Racing Headers provided us with a set of their 1-7/8 primary headers with a 3 inch off-road X-pipe for our CJ racecar. Since the car is not for street use and is mainly for drag racing, we do not need the catalytic converters and wanted the additional power and sound that comes with deleting the cats. The overall tone is very aggressive. With quality components, excellent fitment, solid power gains and an aggressive tone, you can't go wrong with a set of American Racing Headers for your Mustang.